Covered Pool

ABSTRACT

A pool and mechanisms for raising and lowering a platform mechanism within the pool can include a water container with an open top defined by a peripheral edge, a bottom, and at least one sidewall. One or more receiving cavities can be arranged in the bottom of the water container. The bottom can have a contour shape with a first downward slope between the sidewall and a lowest point in the bottom and a second downward slope between the single receiving cavity and the lowest point. The lowest point can include an egress port from the water container. One or more platforms can have a top side and a bottom side and be being sized and adapted to fit within the peripheral edge of the water container. A single column connected with the bottom side of each platform and arranged in a corresponding single receiving cavity can be at least partially displaceable from the single receiving cavity to move the corresponding platform upward and at least partially replaceable in the single receiving cavity to move the corresponding platform downward.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation-In-Part of co-pending application forU.S. patent Ser. No. 11/716,576 entitled, “Covered Pool” which was filedon Mar. 12, 2007 and which is incorporated by reference herein in itsentirety. This application also claims the benefit of U.S. ProvisionalPatent Application Ser. No. 60/781,898 which was filed on Mar. 13, 2006and which is incorporated by reference herein in its entirety.

BACKGROUND

The present invention relates to, but is not limited to, the fields ofconstruction and use of pools and covered pools. Pools may include, butare not limited to, swimming pools, hot tubs, pools used for therapy,reflecting pools, wave pools, whirlpools, and wading pools.

A variety of pools that can be built on a property or purchasedready-made are available. These pools are popular and are often adesired home improvement project.

Many of the available options for providing a pool on a property havedisadvantages. For example, they may require a large piece of open land,which is then used solely for a pool. Unfortunately, many homes or otherareas where a pool might otherwise be desirable do not have a largepiece of land available for dedication for use as a pool. Many availablepools are also expensive and/or inefficient to construct. They may alsobe expensive to heat to a desired temperature. Once a desiredtemperature has been attained, maintaining that temperature may bedifficult. Furthermore, when a pool is not in use debris may accumulatein the pool, or chemicals that are used to maintain a clean, sanitarypool may be degraded by sunlight.

SUMMARY

In a first aspect, a pool includes a water container having an open topdefined by a peripheral edge, a bottom, and at least one sidewall. Asingle receiving cavity being arranged in the bottom of the watercontainer. The bottom has a contour shape that includes a first slopewith a first downward pitch between the sidewall and a lowest point inthe bottom and a second slope with a second downward pitch between thesingle receiving cavity and the lowest point. The lowest point includesan egress port from the water container. A platform with a top side anda bottom side is sized and adapted to fit within the peripheral edge ofthe water container. A single column connected with the bottom side ofthe platform and arranged in the single receiving cavity is at leastpartially displaceable from the single receiving cavity to move theplatform upward and at least partially replaceable in the singlereceiving cavity to move the platform downward.

In an interrelated aspect, a pool includes a water container that has anopen top defined by a peripheral edge, a bottom, and at least onesidewall. Two or more platforms, each with a top side and a bottom side,are sized and adapted to fit adjacently within the peripheral edge ofthe water container. Two or more receiving cavities are arranged in thebottom of the water container. Each of the two or more receivingcavities is sized and adapted to receive a corresponding single columnconnected with the bottom side of a corresponding one of the two or moreplatforms. One or more water flow mechanisms flow water into the two ormore single receiving cavities to at least partially displace thecorresponding single column from its single receiving cavity to move thecorresponding platform upward and to flow water out of the two or moresingle receiving cavities to at least partially insert the correspondingsingle column further into its single receiving cavity to move thecorresponding platform downward.

In a third interrelated aspect, an apparatus is provided for use with apool that includes a water container having an open top defined by aperipheral edge, a bottom, and at least one sidewall, a single receivingcavity arranged in the bottom of the water container. The bottom has acontour shape that includes a first slope having a first downward pitchbetween the sidewall and a lowest point in the bottom and a second slopehaving a second downward pitch between a second point on the bottom andthe lowest point. The lowest point includes an egress port from thewater container. The pool also includes a water flow mechanism to flowwater. The apparatus includes a platform with a top side and a bottomside. The platform is sized and adapted to fit within the peripheraledge of the water container. A single receiving cavity is adapted to bearranged at the second point in the bottom of the water container. Thesingle receiving cavity includes or is associated with a mechanism toreceive and expel water from the water container. A single column isconnected with the bottom side of the platform and placed in the singlereceiving cavity. The single column is configured to be at leastpartially displaced from the single receiving cavity to move theplatform upward when the water flow mechanism flows water in to thesingle receiving cavity, and configured to be at least partiallyreplaced in the single receiving cavity to move the platform downwardwhen the water flow mechanism flows water out of the single receivingcavity.

In optional variations, one or more of the following features can alsobe included. A cross-sectional shape of at least a portion of an outersurface of the single column can correspond with a cross-sectional shapeof at least a portion of an inner surface of the single receivingcavity. The cross-sectional shape of the outer surface of the singlecolumn and the cross-sectional shape of the inner surface of the singlereceiving cavity can be a shape selected from a circle, square,triangle, ellipse, rhombus, trapezoid, or parallelogram. A water flowmechanism can be included to pump water into the single receiving cavitybelow the single column to at least partially displace the single columnfrom the single receiving cavity and to pump water out of the singlereceiving cavity to at least partially replace the single column intothe single receiving cavity. The water flow mechanism can include atleast one pump, an inlet into the single receiving cavity, and an outletfrom the single receiving cavity. The second downward pitch can begreater than the first downward pitch.

The sidewall can include a plurality of interlocking blocks such thateach block has at least one groove that, when aligned and combined withat least other groove on an adjacent block, defines a channel. Each ofthe plurality of blocks can be formed of foam. The water container caninclude a unitary piece that includes the peripheral edge, the bottom,and the at least one sidewall. The unitary piece can include one or morematerials selected from plastic, fiberglass, fiber-reinforced material,stainless steel, metal, and foam. The single column can include apressure release channel having an inlet in the bottom of the singlecolumn and an outlet on the outer surface of the single column at adistance above the bottom of the single column.

The pressure release channel can be configured to allow water to flowfrom the single receiving cavity into the water container when theoutlet of the channel extends above a top edge of the single receivingcavity to release a predetermined amount of pressure in the singlereceiving cavity. The single receiving cavity can include a singleaperture proximate a bottom of the single receiving cavity that definesthe inlet into and the outlet from the single receiving cavity. Thesingle column or columns can be at least partially displaced from thereceiving cavity or cavities when water received into the receivingcavity produces a pressure that exceeds a threshold pressure that canoptionally be 5 or 10 pounds per square inch. A pool deck controller cancontrol raising and lowering of the platform or platforms by passingcommands to the water flow mechanism or mechanisms. The pool deckcontroller can optionally raise and lower the two or more platformsindependently of each other or in a coordinated manner.

The details of one or more embodiments are set forth in the accompanyingdrawings and the description below. Other features and advantages willbe apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects will now be described in detail with referenceto the following drawings.

FIG. 1 depicts a pool that is one embodiment of the invention.

FIG. 1A depicts a cast polymer side for use in forming a pool sidewallof the invention.

FIG. 2 depicts a top view of a block used to form a sidewall of theinvention.

FIG. 2B depicts additional top views of sidewalls for use in theinvention.

FIG. 2C depicts additional top views of sidewalls for use in theinvention, including automatically joining sidewalls, with male andfemale connectors.

FIG. 3 depicts a top view of a sidewall formed from blocks of theinvention.

FIG. 4 depicts a top view of a block and a portion of a sidewall formedfrom similarly-shaped blocks.

FIG. 5 depicts a top view of the interface of two sidewall blocks.

FIG. 6 depicts sidewall blocks including lights (6A), swim jets (6B),and a skimmer (6C).

FIG. 6D depicts top views of rooms that may be made according toembodiments of the invention.

FIG. 7 depicts a bottom view of a cover of the invention.

FIG. 8 depicts (A) a top view of a cover of the invention, with asupport framework shown in phantom view; (B) a top view of a singlepanel with two segments; and (B) a side cutaway view of a segment.

FIG. 8A depicts a patio surface with a seal, an edge thicker than thecenter, and a web support including fiberglass rods.

FIG. 8B depicts a further top and side view of a patio surface with aseal that will contact the coping. A fiberglass and resin structureincludes optional foam inserts.

FIG. 9 depicts a panel that may be used to form a cover of theinvention.

FIG. 10 depicts a hub and spoke frame for supporting a cover.

FIG. 11 depicts a partial side view of a hub and spoke frame shown inFIG. 10 (bottom) and a side view of a spoke (top).

FIG. 11A depicts a top view of a rim and panel for a cover, with a sideview of a hub.

FIG. 12 depicts the top view of a hub, spoke and rim framework.

FIG. 12A depicts a top view of a rim and legs configuration of a supportcover of the invention.

FIG. 13 depicts a side view of a support arm bolted to a beveledframework rim.

FIG. 13A depicts a top view of a rim, side view of a hub, and top,front, reverse, and side views of support arms.

FIG. 13B depicts a top, front, reverse, and side view of a support arm.

FIG. 13C depicts a front view of a support arm of FIGS. 13A and 13B.

FIG. 13D depicts a front view of another possible support arm.

FIG. 14 depicts a number of possible support frameworks for use in theinvention.

FIG. 15 depicts a top view (A) and a side view (B) of coping used in anembodiment of the invention.

FIG. 16 depicts one example of a multiple-stage hydraulic cylinder foruse as a lifting mechanism in the invention.

FIG. 17 depicts another example of a multiple-stage hydraulic cylinderfor use as a lifting mechanism in the invention.

FIG. 17A depicts a further example of a multiple-stage cylinder.

FIG. 17B depicts a further example of a multiple-stage cylinder.

FIG. 17C depicts a top view of a cylinder of the invention.

FIG. 18 depicts a side cutaway view of a sealed interface for areceiving cylinder and hydraulic cylinder of the invention.

FIG. 19 depicts a side cutaway view of another sealed interface for areceiving cylinder and hydraulic cylinder of the invention.

FIG. 20 depicts a flow diagram for a pump used in an embodiment of theinvention.

FIG. 20A depicts a scissor lifting mechanism for use in the embodimentsof the invention.

FIGS. 21C and 21D, which join from left to right, depict an operationsdiagram for a pool of the invention, including filters, pumps, lighting,and exhaust.

FIG. 21 depicts a pin brake that may be used in an embodiment of theinvention.

FIG. 22 depicts a bladder brake that may be used in an embodiment of theinvention.

FIG. 22A depicts an actuated braking mechanism.

FIG. 23 depicts a side view of a pool of the invention with a singlecylinder hydraulic lifting mechanism as well as additional hydraulicsupports.

FIG. 23A depicts another side view of a pool of the invention with asingle cylinder lifting mechanism. A partial side view of the undersideof a platform is also shown.

FIG. 23B shows a detail of the central portion of a pool of FIG. 23A.

FIGS. 23C, 23D, and 23E show additional views of support cylinders asshown in FIG. 23.

FIG. 24 depicts a cutaway top view of a rack and gear assembly forstabilizing a cover of a pool of the invention.

FIG. 24A depicts a side cutaway view of a rack mounted to a centerpiston as the receiving end of a locking mechanism.

FIG. 24B shows a further embodiment of lifting, locking and failsafemechanisms.

FIG. 24C shows a further embodiment of lifting, locking and failsafemechanisms.

FIGS. 24D, 24E, 24F, and 24G show an additional stabilizer.

FIG. 25 shows pools of the invention in various shapes.

FIG. 26 shows pools of the invention in tandem with conventional pools.

FIG. 27 shows a typical control diagram.

FIG. 28 shows a typical control box.

FIG. 29 shows a cross-section of one preferred implementation of a poolwith a movable cover.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

One embodiment of the invention is shown in FIG. 1. A pool of theinvention may comprise, for example, a structure 1 for containing water(usually comprising a bottom 3 and one or more sidewalls 5), a cover 7having a top side and a bottom side, and a mechanism 9 for raising andlowering the cover. When the cover is lowered beneath the water level,it provides a false bottom for the pool of water that is formed. Theseand other elements will now be discussed in greater detail withreference to the figures. It should be noted that the top and bottom ofthe cover are used as points of reference only, and that it should notbe meant to imply (or to exclude) a certain number of layers in theconstruction of the cover.

A. Bottom and Sidewall(s)

Pools of the invention have at least one bottom and at least onesidewall. Because the pool is intended to hold water for a long periodof time, the bottom and sidewalls of the pool should be substantiallywatertight. Ideally, the bottom and sidewalls are completely watertight.The bottom and sidewalls of a pool of the invention should be able towithstand the pressure of the stored water and/or provide adequatecounter pressure against the pressure that is exerted by the storedwater inside the pool.

A variety of materials may be used to construct the bottom and sidewallsof the invention. These materials include, for example, concrete,cement, foam or plastic. In a preferred embodiment of the invention,shown in FIG. 1A, the sidewalls of a pool include or are composedentirely of a cast polymer. This cast polymer may have one or morehollows or indentations that allow insertion of insulation into thepolymer. The bottom and sidewalls do not need to be made of the samematerial. The bottom and/or sidewalls may be covered by a liner. Theliner may be a plastic liner. In some embodiments, the bottom is soilcovered by a liner.

In one embodiment, the sidewalls are constructed of materials thatinsulate and/or that retain heat. These materials may be, for example,hard foam. Hard foam is, for example, polyester foam or polyethylenefoam. Hard foam blocks may be molded in the shape for constructing thebottom and sidewalls. Hard foam blocks may also be cut into the shape.For example, hard foam blocks may be cut with computer numericallycontrolled (CNC) machines. Ideally, the blocks will be formed so thatwhen placed into position in the hole where the pool is to beconstructed, the desired shape of the bottom and sidewalls is formed. Inone embodiment, a foam block is hot-wire cut from a 6′×6′×8′ foam block.

The shape of each block will, of course, depend on the overall desiredshape of the pool. For example, for a circular pool, one could calculatethe desired interior diameter, desired outer diameter, and desirednumber of blocks. Properly cut blocks will allow fine assembly at seamsof the blocks.

In a further embodiment, grooves may be cut and/or formed through andalong each side of the sidewall components (blocks). When the blocks areoriented to form the bottom or sidewalls of the pool, the groovesprovide a series of connecting channels. These channels may be filled orpartially filled to provide a framework for the sidewalls that increasesstability of the sidewalls. The channels may be filled, for example, byconcrete, urethane, polystyrene, fiberglass-reinforced compounds, orepoxy, or mixtures of these. Rebar may also be inserted into thechannels to increase stability. The material in the channels may act asa bonding agent that hardens and that holds the blocks together in astructural grid. Blocks may also have alternating grooves andprotrusions that allow them to interlock. After the blocks have beeninterlocked, they may further be secured by application of one or morestraps or belts around the outer perimeter. These straps or belts maybe, for example, steel or stainless steel.

FIG. 2 shows one example of a top view of a block 13 that includesgrooves 15 for creation of stabilizing channels. FIG. 3 depicts a topview of a sidewall 15 formed by foam blocks 13, and including channels17. FIG. 4 depicts a block 19 that is shaped differently from the blockof FIG. 2, along with a portion of a sidewall formed from that block.FIG. 5 depicts the interface of two blocks 21 with interlocking male 23and female 25 connectors. The blocks of FIG. 5 include a tile overlay27. The channel 29 has been filled in FIG. 5 to provide stability.

Channels may be cut through the blocks. If these channels intersect withchannels cut along the side of the blocks (and therefore with thechannels that are created), then a bonding agent that is placed in thechannels will further provide a stabilizing framework for the sidewalls.

Foam blocks used to form the bottom and sidewalls may be finished with awatertight or water-resistant coating prior to being placed intoposition in the hole where the pool is constructed. If desired, they maybe finished after being placed into position in the hole where the poolis constructed.

Foam block construction has a number of advantages. Foam blocks aredurable and are resistant to cracking or breakage due to groundmovement. The density of foam blocks may be, for example, but is notlimited to, 1 lb/cubic foot or 2 lb/cubic foot. This allows the blocksto act as insulators. This insulation may reduce the cost of heating thepool. Foam blocks are also light, allowing the pool components to becarried and installed by a small team of people, perhaps as few as oneor two.

Foam block construction further allows the pool to be repaired withoutdoing significant damage to the pool's watertight interior. When aproblem arises with an apparatus on the pool's interior, the apparatusmay be accessed from the side of the sidewall opposite the watertightcoating. After the apparatus has been serviced, the foam block may berepaired using foam that is blown into the breach created to service theapparatus.

Foam blocks may be prefabricated so that they include various featuresuseful in a pool and/or so that they are ready to accept such featuresand apparatuses. For example, they may be prefabricated to includepiping, wiring, heating, filtration (including skimming), pumping, swimjets, vortex jets (that is, jets that create a “whirlpool”), massagejets, speakers, hot tub jets, a massage jet harness attachment,lighting, recessed ladder or stairs, ladder recesses, brake detents,tile or combinations of these features.

These features may be designed to be interchangeable. Interchangeabilitywould allow an existing pool of the invention to be upgraded. Forexample, a pool without lighting or swim jets may be adapted to includethem by replacing all of or a portion of a foam block. Use of foamallows access to the back of the walls, so that the portion facing thewater can remain watertight. A liner might also be inserted duringrepair.

FIGS. 6A, 6B, and 6C show blocks prefabricated to include lights, swimjets, and a skimmer, respectively. In one embodiment, a customer who ispurchasing a pool is given a blank form depicting the availablesidewalls of his pool. The form may be similar, for example, to FIG. 3.Each available feature (as well as “no feature”) is assigned a numberand a price, and the customer selects a number for each block in theform. In this way each customer can create an individualized poolexperience.

In one embodiment, at least one massage jet and a massage jet harnessare included in the sidewall. Preferably 4 or 5 massage jets aredisposed in a block in an orientation amenable to massaging, forexample, a person's back. To enable the person to maintain position inan area where the jets would be effective, the block may also include atether for a harness that a person may wear while using the massagejets. Each massage jet may operate, for example, using a motor withabout 2 to about 3 horsepower, though this number can be varied at thediscretion of the user. The massage jets may have a variable intensitycontrolled by a panel either integral to or separated from the pool. Themassage jets may be controlled remotely.

Although the foam block pool construction has been described in thecontext of creating a covered pool, the principles of foam block poolconstruction as recited herein may be applied to construction ofconventional pools as well.

Although block construction has been thus far described herein in thecontext of pool formation, it is also useful in construction of otherstructures. In one embodiment, the use of interlocking foam blocks thatare reinforced with rebar or fiberglass as well as poured concrete intocavities in the foam is provided to create a structure that acts as apartial or complete “outdoor room” environment. The blocks themselvesmay contain cutouts where appropriate outdoor features can beincorporated, including televisions (including optional tilt functions),DVD/VCR players, stereos, speakers, USB ports, remote control(including, optionally, remote mouse controls), heating and coolingvents, jets, or ducts, natural gas or propane fireplaces, lightingfixtures, and fountains. Sections of this interlocking block structurecan be used for seating and/or as display areas for plants and statuary.The foam blocks themselves can be finished with a variety of coatingsincluding but not limited to stucco, plaster, tile, artificial or realrock or other similar veneers.

The structure can be secured into the ground with at least two concretefootings that are poured through cavities in the appropriate blocks.Pouring concrete into cavities that when set irrevocably connects two ormore such foam blocks provides additional structural stability. Thepreferred structure includes an arc of a circle of at least a 12 footdiameter and may create a complete circle. Alternatively the structuremay also include at least two tight angles and may also include a 45degree angle across the square (as shown in diagram attached), or couldbe fully enclosed into a rectangular or square room. FIG. 6D shows anumber of possible outlines for structures of this embodiment of theinvention. The structure may further include a tube substructure aboutthe outside of the wall, allowing hot, compressed air to be pumped intothe room. When coupled with a heater, this could provide an inexpensive)efficient way to heat such a room.

A roofing structure is also contemplated in certain manifestations ofthis invention. This roofing structure may also incorporate a fan withor without water misting features. This structure may be used topartially or completely surround a telescoping table and/or asubmersible patio pool/spa of a described herein.

Rooms of this embodiment may provide a number of features. The use ofprefabricated interlocking foam blocks provides a structural materialthat is well insulated, lightweight and inexpensive. This structure ismade substantially stronger and more durable by the addition of rebar orfiberglass as well as poured concrete into these prefabricated foamcavities, and further strength and stability is provided by the arcdesign. When coated, the structure will not rot or deteriorate. Thenature of this process allows for a structure to be created on-site morerapidly, for less cost and with greater durability and sound and heatinsulation than could be provided using traditional constructionmethods. The prefabricated cutouts in these foam blocks allow for rapidand reliable insertion of desired appliances.

The combination of this structure with a telescoping table and/or patiopool as described above substantially increases the flexibility of asmall living space by creating a room/area that can be used for avariety of activities including home theater, dining, swimming,playroom, or a combination of all four. The superior heat and soundinsulation provided by the foam blocks creates a uniquely intimateenvironment for all of these activities that cannot be achieved usingexisting construction methods. The rapid ability to change the functionof a room or space by employing the telescoping table and/or patio poolin combination with the new construction methods described here does notcurrently exist in industry and provides a potential benefit to homeowners with limited space.

B. Cover

The invention includes a cover. The cover may be rigid or semi-rigid. Ofcourse, those skilled in the art will recognize that all materials havesome amount of rigidity, but a minimal flexibility is preferred. In someembodiments, the cover has a top side and a bottom side capable ofcovering or substantially covering the open top of the pool. The coveris able to move to and from the bottom of the pool along the sidewallsof the pool by raising and lowering.

The bottom of the pool may be flat. Preferably, the bottom of the poolhas areas of varying elevation. Varying the elevation allows anysediment or other waste that enters the pool to collect in an area whereit might more conveniently be removed by a debris suction device. Oneexample of a bottom of varying elevation is shown in FIG. 1, wheredepressions 11 provide an area for accumulation of debris.

In one embodiment, the cover does not contact the sidewalls of the pool,resulting in a gap between the cover and the sidewalls. For example, theperimeter of the cover may be between about 0.25 inches and 2 inches,preferably 1 inch, away from the sidewalls of the pool. The gap betweenthe cover and the sidewalls may be, but is not required to be, uniformabout the perimeter of the cover. In some embodiments of the invention,the separation of the cover and the sidewalls allows water to flow fromthe area beneath the cover to the area above the cover as the coverlowers, and to flow from the area above the cover to the area below thecover as the cover raises. In a further embodiment, there is no gapbetween the cover and the sidewalls (or between the seal and thesidewalls), and water is able to flow through one or more holes in thecover.

In a yet still further embodiment, the cover includes one or more holesthat have flaps or valves. These allow additional flow of water so thatthe cover may raise and lower at a faster rate than it might otherwiseraise or lower.

In another embodiment of the invention, the cover has a width that issmall compared to that of the pool. In this case, the cover, whenraised, may act as a support for an additional lightweight top that isplaced over the cover. This top may provide strength and coveragesufficient to prevent debris from entering the pool. Although in thisembodiment there might not be sufficient strength to place things on thecover, but it is still sufficient to prevent debris from entering thepool.

The perimeter of the cover may be surrounded by a flexible seal. Thisseal may be in continuous contact with the coping of the pool (describedmore fully below) when the cover is in its highest position. After thecover lowers below the level of the coping and before the cover lowersto the water level, there is a gap between the seal and the sidewalls.This gap allows flow of water from below the cover to above the cover asthe cover lowers. When the cover raises, the flow is reversed.

In a further embodiment this seal is in continuous contact with thesidewalls as the cover lowers and raises, and while the cover is atrest. In this embodiment, the cover includes holes that allow water toflow from one side of the cover to the other as the cover lowers orraises.

The cover may be of a single construction. The cover may also beconstructed from two or more panels. Each panel may further be dividedinto segments. A circular panel may be constructed, for example, asshown in FIG. 7 and in FIG. 8. In FIG. 8, panel 31 includes segments 33and 35. The spaces 37 between panels and 39 between segments may besealed or may be left open. If left open, the spaces will allow flow ofwater when the cover lowers or raises. The spaces may be sealed, forexample, by pool grout. The center of the cover may include a cap 41.The panels and/or segments may also be interlocking. Another panel isdepicted in FIG. 9.

The cover may include one or more access ports that allow access to thearea between the bottom and the cover. When the cover is constructedfrom multiple panels and/or multiple segments, it is convenient to havea single panel or a single segment serve as an access port formaintenance or other purposes. This panel may be designed to be looselyaffixed or released as the cover lowers into the pool, so that water mayflow around the panel.

The cover may include an ornamental design on the surface. Thisornamental design may be, for example, mosaic, tile, a modern motif, anantique motif, or a western motif. The cover may be cast so that itincludes space for addition of tiles.

The cover may be made from any suitable material. For example, the covermay be constructed from casting material. Casting material may include,for example, concrete, fiberglass, resin, or combinations of those.Filler materials may also be included to reduce the mass of the cover.Filler materials include, for example, clay beads, or glassmicrospheres. In one embodiment, the cover is made from a mixture ofepoxy, sand, pebbles, and glass microspheres. Preferably, the cover (orpanels, or segments) is light enough to be lifted, moved, and assembledby no more than two people.

In one embodiment of the invention, both the top and the bottom of thecover are flat. In another embodiment, the bottom of the cover includesribs 43, as shown in FIG. 8. These ribs increase the strength of thecover while still allowing portions of the cover to be thin and lightenough for the cover to be lifted by no more than two people.

C. Framework

Where the cover is a single piece, it may rest directly on the mechanismused to lower and raise the cover. When the cover is constructed frommultiple pieces, the cover ideally is supported by a framework. In oneembodiment of the invention, the framework is a rim and leg framework asshown in FIG. 10. The rim and leg framework includes a plurality ofsupport legs 45 extending from a rim 47 at the center of the cover tosubstantially the periphery of the cover. This divides the cover into aplurality of sections.

The rim and leg framework may be made of any material substantial enoughto support the weight of the cover and of any people and/or equipmentthat may be placed on the cover when in the raised position. The rim andthe legs may be of the same material or different material. Thismaterial may be, for example, stainless steel, aluminum, titanium,fiberglass, resin, or plastic. The rim and the legs may be coated with amaterial to help increase resistance to corrosion. For example, they maybe coated with a fiberglass-reinforced polymer. Thisfiberglass-reinforced polymer may be, for example, epoxy.

The rim and leg framework may be created by fastening individual supportlegs to the rim. The rim is then attached to a central hub. In analternative embodiment, support legs are attached directly to the hub.One suitable support leg is shown in FIG. 11. The rim or hub may then bebolted to the lifting mechanism, described below. One such liftingmechanism, a hydraulic cylinder 49, is shown in FIG. 10. Upon insertioninto the hub, the support legs may be secured into the hub.

In a preferred embodiment, each pair of legs supports a single panel.Legs may also be situated so that there are one or more legs under eachpanel.

In a further embodiment of the invention, each leg is reinforced bymultiple sheets of material. One preferred material for thisreinforcement is extended steel. Each leg may further be provided withan attaching mechanism, as shown in FIG. 11A. This allows the legs to befurther secured, if desired or necessary. Extended steel legs may havemultiple layers of extended steel. They may further be reinforced byepoxy, resin, or another substance.

In a further embodiment of the invention, the framework is a hub, rim,and wedge framework. An example of a hub, rim, and wedge framework isshown in FIG. 12, which shows a hub 51, a plurality of wedges 53, and arim 55. Another example is shown in FIG. 12A. Although the rim may becircular for maximum strength, it may be other shapes if desired. Thehub, rim, and wedge framework may be individual interlocking pieces orit may be created as a single piece.

A wedge may be constructed to include one or more radiating legs, asshown in FIG. 12A. Portions of each wedge may be the same material ordifferent materials. For example, the radiating legs included in thewedge may be steel coated with a corrosion-resistant material. Thismaterial may be, for example, a fiberglass-reinforced resin. Thearctuate member of each wedge may be stainless steel or aluminum, forexample.

In a preferred embodiment, the rim is five feet in diameter and made ofaluminum. Additional stability may also be provided by adding additionalcrosspieces 57, as shown in FIG. 12. The rim may also be made, forexample, from stainless steel, fiberglass, titanium, or other materials.If additional support is desired, further spokes (support arms) may beplaced along the perimeter of the rim, as shown in FIG. 13. These spokesmay have beveled tops that correspond with similar beveling on the rim.In a preferred embodiment, each further spoke is secured by two bolts,as shown in FIG. 13. FIG. 13A depicts a top view of a rim, side view ofa hub, and top, front, reverse, and side views of support arms, whichmay be, for example, a combination of fiber composite, steel, andstainless steel. FIG. 13B depicts a top, front, reverse, and side viewof a support arm. FIG. 13C depicts a front view of a support arm ofFIGS. 13A and 13B. It includes rebar, a stainless steel top, a stainlesssteel backplate, a steel stabilizing tube, a resin flu, and a fiberglasswaterproofing. FIG. 13D depicts a front view of another possible supportarm, including a stainless steel endcap.

Additional rim designs are shown in FIG. 14. The central hole of the rimmay be tapered to match a corresponding taper of the cylinder.

Use of a framework to support the cover has a number of advantages. Forexample, use of a geometric framework allows a minimum number of panelsto be affixed to the framework, providing a large-sized cover. Becausethe panels can span edge to edge without direct support from the centerof the framework, they can be assembled by dropping them into place andsecuring them. Panels may be secured, for example, by pins, screws,bolts, protrusions in the casting, or other ways that will be recognizedby those skilled in the art with the benefit of this disclosure.

In one embodiment of the invention, the cover may include a separatepiece that can be raised independently of the remainder of the cover.This separate piece may be located anywhere on the cover and may be anyshape. Ideally it is located in the center of the cover and is circular.The separate piece may even be raised above the maximum level of thecover. The separate piece may be used as a table when the cover is inany position. For example, the cover may be lowered so that there isabout one foot of water above the surface of the cover, and the tablemay be raised about three feet above the level of the cover. This wouldallow a user of the pool to sit at the table and eat or perform otheractivities, while still soaking his feet in the pool.

The mechanism used to raise and/or lower the separate piece may beseparate from or integral to the mechanism used to raise and/or lowerthe cover. For example, where the separate piece is a central table, thetable may be raised by a separate piston in the central cylinder.Preferably, the table is raised by a separate cylinder that is situatedin a separate hole in the cylinder. In this preferred embodiment thetable has its own water supply and is able to be raised and loweredentirely independently of the cover. In such a preferred embodiment, thecylinder for raising and lowering the table is about 50 inches long.Lift cylinders for embodiments of the invention are provided in moredetail in Section E, below.

The lift technology described herein may be used to make a table thatraises and lowers and is not associated with a pool. This may be useful,for example, where a user has a small yard and wishes to have a tableavailable but hot always present. A lift cylinder could be embedded inthe ground and provided with a water pump and supply. Optionally, acover could be provided that would simulate the surrounding greenery. Inthis way the table could be completely out of sight when not in use.

D. Coping

The sidewalls of the pool may include pool coping. The coping providesfinished edges. If desired, the coping provides a seal with the cover.This allows the cover to seal the pool when in or near the highestraised position. FIG. 15 shows a top and side view of coping in oneembodiment of the invention. Gasket-type devices, including inflatablegaskets, materials, and methods, may be used to tighten the seal betweenthe coping and the cover. This may prevent debris from entering thepool.

A variety of copings may be used in the invention. In one embodiment, acustom coping is installed by an artisan who is skilled in stoneworking.In a preferred embodiment, a coping is cast from a mold. The cast copingmay be one or more pieces. These pieces may be assembled on-site,allowing significant portability of the coping. Coping may be made, forexample, from cement, concrete, stone, or other material.

Coping may include one or more holes for attachment of a ladder. Thisladder may be placed in the pool following lowering of the cover to adepth where a ladder is necessary or desirable. A sidewall may furthercontain one or more detents for securing a ladder. The ladder may beprovided with a failsafe to prevent the ladder from interfering with theraising or lowering of the pool. For example, the ladder may be designedto break away if contacted by the cover, or it may sound an alarm if thecover is raised within a certain proximity.

E. Mechanism(s) for Elevating and Lowering the Cover

The cover of the pool may be raised and lowered by a user to allow waterto flow from one side of the cover to the other. In a preferredembodiment, when the cover has been raised to its maximum level, thecover is above the surface of the water and flush with the surroundingarea. The cover may then be used, for example, as a patio. When thecovet is lowered to its lowest level, the maximum pool depth isavailable.

The pool may also be designed so that it is capable of stopping at oneor more levels between the maximum level and the minimum level. Whenstopped at these levels, the pool may provide water of various apparentdepths based on the position of the cover relative to the surface of thewater. For example, when the cover has been lowered from its maximumlevel such that only a small amount of water is on the upper side of thecover, the pool may be used as a decorative reflecting pool, a wadingpool, or a child's play pool. At levels closer to the minimum level, thepool may be used as a hot tub, a whirlpool, or a therapy pool. A pool'scontrol mechanism may be configured to allow the pool to stop at anypoint designed by the user. It may also be configured to allow the poolto stop at any of a number of specified depths.

The mechanism for raising and lowering the cover may be any mechanismsufficient to lift the cover when it is at its minimum elevation (andtherefore under the greatest amount of water). Although the cover may belowered slowly by gravity depending on the density of the cover, it ispreferable that the mechanism provide force to lower the cover. Themechanism may be any manual, automated, and/or motorized mechanism. Thismay include, for example, pulleys, gears, scissor lifts, air pillows,hydraulics, or combinations of these. Although the description generallydiscusses a single mechanism, it will be understood that more than onemechanism may be used in tandem, or that a failsafe mechanism may beincluded to raise the cover in case of failure of the primary mechanismor in case the cover needs to be raised very rapidly. The mechanism forraising and lowering the cover may be completely contained beneath thecover of the pool.

The mechanism may raise and lower the cover by exerting a force from thetop, side, and/or bottom of the cover. It may also raise or lower thecover by exerting a force from one or more locations on or about theperiphery of the cover.

In one embodiment, the lifting mechanism is at least one hydrauliccylinder. A hydraulic cylinder is connected to the bottom of the poolcover or the bottom of the framework. The hydraulic cylinder is aone-stage cylinder or a multiple-stage cylinder. The multiple-stagecylinder may be a telescopic cylinder. A telescopic hydraulic cylinderincludes sections of tubing with successively smaller diameters. Thesesections nest inside, which results in a smaller housing being requiredfor the hydraulic cylinder. When a telescoping hydraulic cylinder isactivated to raise the cover, the largest stage, with the smaller stagesinside it, will move first, and this continues for each stage until thetelescopic hydraulic cylinder is fully extended. When retracting, thesmallest-diameter stage retracts before the next stage starts moving.

One example of a multiple-stage hydraulic cylinder for use in theinvention is shown in FIG. 16. Further examples are shown in FIG. 17Aand FIG. 17B. A lifting mechanism using this multiple-stage hydrauliccylinder could be placed in a hole as shallow as 24 inches in the bottomof the pool.

FIG. 17C shows an additional cylinder for use in the invention. In FIG.17C, a central cylinder 58 is surrounded by a plurality of foam prisms60 having a trapezoidal cross section. These prisms 60 are wet-coatedwith a layer of fiberglass 62, and foam prisms 64 having a triangularcross-section are inserted into the spaces between the prisms 60. Afurther layer 66 of fiberglass is applied. FIG. 17C also shows an endcap 66, including hexagonal bolt attachments, superimposed on thecylinder.

Another example of a hydraulic cylinder for use in the invention isshown in FIG. 17. The hydraulic cylinder assembly in FIG. 17 includes areceiving cylinder 59 that surrounds a first hydraulic cylinder 61 and asecond hydraulic cylinder 63. The interface of the receiving cylinder 59and the first hydraulic cylinder 61 is sealed by an O-ring 65.Connection of the second hydraulic cylinder to the framework 67 occursat 69. The hydraulic cylinder further includes an optional threading rod71 that may be used to adjust the default height of the hydrauliccylinder. The threading rod may be a stainless steel threading rod. FIG.17 also shows the flow inlet 73 from the pump (not shown).

A hydraulic cylinder for use in the invention may be constructed, forexample, from plastic, aluminum, fiberglass, stainless steel, or othermaterials. In one embodiment, the hydraulic cylinder is a plasticcylinder with a stainless steel sheath. In a further embodiment, thehydraulic cylinder and the receiving cylinder (described below) havecurved grooves. These grooves allow the pool cover to rotate as itraises and lowers. This may provide a pleasing visual effect.

The bottom of the hydraulic cylinder is contained in a receivingcylinder. The receiving cylinder is recessed into the bottom of thepool. The receiving cylinder may be constructed of the same material ordifferent material than the hydraulic cylinder. The receiving cylindermay be, for example, stainless steel, plastic, polymer, fiberglass,aluminum, or other suitable material. Preferably the receiving cylinderis a plastic cylinder with a stainless steel sheath. Preferably theinner diameter of the receiving cylinder is no more than 10/10,000 toabout 50/10,000 greater than the outer diameter of the hydrauliccylinder. Ideally the difference will be as small as possible.

Any suitable fluid may be used to exert hydraulic pressure in thehydraulic cylinder. For example, the hydraulic cylinder may containhydraulic fluid, olive oil, or water. Water is preferred as the fluidused to exert the hydraulic pressure. When the hydraulic cylindercomprises water, leakage of the hydraulic cylinder is of little concern,because the leaking water in the cylinder will merely mix with the waterof the pool. Controlled leakage may be beneficial, because it can allowthe water in the hydraulic cylinder to be exchanged on a regular basis.The hydraulic cylinder may also be equipped with a backflow valve toallow the fluid to be replaced.

Those skilled in the art will recognize that the hydraulic cylinder andthe receiving cylinder should meet at a sealed interface to preventleakage of the fluid used to provide the hydraulic power. A cutaway viewof one sealed interface is shown in FIG. 18. In this sealed interface,an O-ring 75 is situated between the receiving cylinder 77 and anultra-high molecular weight polyethylene (UHMW) strap 79, with a furthertensioning strap 81. In one embodiment, the receiving cylinder and thefurther tensioning strap are stainless steel. The interface is filledwith epoxy, silicon, or another sealant 83 and secured with a pressureplate 85 that is secured to the epoxy. In one embodiment, the pressureplate and the bolts 87 that secure the pressure plate are stainlesssteel. The pool bottom 89 is also shown.

An alternative sealed interface is shown in FIG. 19. The sealedinterface of FIG. 19 includes a gasket 91, which may be a Teflon®gasket. The gasket encloses multiple O-rings 93. The gasket and theO-rings are stabilized by an enclosure 95. The enclosure may be astainless steel enclosure. An optional layer of sealant 97 covers boththe enclosure and the gasket, and a pressure plate 99 is bolted to theenclosure. The pool bottom 101 and receiving cylinder 103 are alsoshown. Preferably the seal may be accessed without removing the cover ofthe pool.

In a further embodiment, multiple hydraulic cylinders are used. Eachhydraulic cylinder may have the characteristics of the single liftingcylinder described above. The characteristics of the multiple cylindersmay be the same or different. This embodiment is preferred forsituations in which more than one portion of the cover is raised orlowered independently of another portion or portions of the cover. Forexample, a rectangular pool and cover could be designed with a hydrauliccylinder at either end of an axis of the rectangle. If the cover is asingle piece, lowering one cylinder to a greater extent than the othercylinder could create a pool with a sloped bottom. If the cover weremultiple pieces able to move independently, lowering one cylinder to agreat extent than the other could create a pool with two differentdepths. If desired, perhaps for safety reasons, pools with cover piecesable to move independently of each other could have the cover piecesconnect by a membrane that would prevent items and people from travelingand/or being trapped under the portion of the cover that has a greaterelevation.

Use of a hydraulic lifting mechanism has a number of advantages. Forceexerted by a hydraulic cylinder is expressed in the simple relationship:

Cylinder Output Force (pounds)=Pressure (psi)×Cylinder Area (in2)

Even a modestly-sized cylinder is able to provide a substantialmultiplier to the pressure that is provided. For example, a cylinderwith a diameter of 12 inches multiplies pressure over 113 times. Acylinder of that diameter would be able to support a weight of over11,000 pounds using a pressure of only 100 psi.

Because of the substantial multiplier provided by an adequately-sizedcylinder, a cover may be raised, lowered, and held in position by acomparatively small water pressure. In embodiments of the invention,this pressure is provided by a conventional pool filter pump; however,if needed or desired, the pressure from a conventional garden hoseshould be sufficient to raise or lower the cover over time. This pumpmay be, for example, a Hayward® brand pump. The pump may be configuredto provide pressure to raise the cover and suction to lower the cover.The same pump (or a different pump) may be configured to operate thepool skimmer as well as any other pressurized pool accoutrements, suchas swim jets or massage jets. One diagram of a pump configuration isshown in FIG. 20.

In a further embodiment, a scissor lift is the lifting mechanism. In apreferred embodiment, the scissor lift is a hydraulic scissor lift. Oneexample of a hydraulic scissor lift is shown in FIG. 20A. In thatexample, multiple legs 100 disposed in tracks 102 have movementcoordinated by gear 104. The legs 100 are raised by hydraulic cylinders106, which may then be used to lock the cover in position.

In a further embodiment, an inflatable bladder is the lifting mechanism.This bladder could be filled with liquid or gas from a remote sourcewhen the cover is to be raised, and air could either be forciblyevacuated or allowed to exhaust naturally when the cover is to belowered. Although this embodiment could be used for any size pool, it isbest suited for a small pool.

In a most preferred embodiment, shown in FIGS. 24B and 24C, a differentmethod of applying fluid force is used as the lifting mechanism. In thisembodiment, a column 108 is disposed in a receiving cavity 110, wherethe cavity has a cross-sectional shape corresponding to the shape of thecolumn. This shape may be, for example, a square, triangle, circle,ellipse, rhombus, trapezoid, parallelogram, or any other shape. In apreferred embodiment the shape is a square, which prevents rotation ofthe cover. Ideally the column is free to travel about the cavity alongits length. At or near the bottom of the cavity are disposed one or morewater inlets (not shown). By “corresponding” to the shape, it is meantthat the shape can be exactly the same, or that the shape of thereceiving cavity can vary from the shape of the column by the amountnecessary to also take in a stabilizing rack or other mechanism.

As water enters the water inlets, it pushes the column, which in turnpushes the cover. This lifts the cover to a desired height, and a valvemay be used to maintain the upward force. As described in Section F,below, further mechanisms (including rack 139 and locking mechanism 141)may be used to stabilize the column and thereby stabilize the cover atthe desired height. When the column (and the cover) are to be lowered,the valve and the stabilizing mechanisms are disengaged, the fluid flowis reversed, and the column and the cover retract.

In a preferred embodiment, the column is tapered, or a portion of thecolumn is removed at the end nearest the bottom of the cavity to providepressure-relief grooves 112. When the column has elevated to the extentthat the taper and/or removed portion is exposed, water is able to flowfreely about the column, preventing the column from rising further thandesired.

F. Mechanism(s) for Stabilizing the Cover

Although no stabilization is required so long as force from the liftingmechanism is maintained, one or more braking devices may be included.These devices may be particularly useful to mimize or prevent slightlocal variations of the cover height at or near the cover's perimeter.In one embodiment of the invention, a hydraulic brake system is attachedto the cover, with multiple brake devices disposed about the perimeter.Preferably, the hydraulic function of the brake system is independent ofthe hydraulic function of the lifting mechanism. Various possible brakesystems for use in embodiments of the invention are shown in FIGS. 21,22, and 23.

FIG. 21 shows a hydraulic pin that may be used as a braking system forthe invention. In FIG. 21 a pin 103 is configured to affix into amatching recess in the sidewall of the pool. The pin may be extended andretracted hydraulically or by mechanical means. In one embodiment, thepin is a stainless steel pin, and the piston 105 is epoxy. The sidewallof the pool may contain multiple recesses at varying heights to acceptthe pin.

FIG. 22 shows an inflatable brake that may be used in the invention. Inthe brake of FIG. 22, a bladder 107, preferably of heavy rubber, isfilled with water or air. This secures a brake pad to 109 the sidewall111 by pressure. The brake pad may be, for example, fiberglass. Thebrake pad may have a coating 113, for example a rubber coating,preferably a rubber coating, at the interface where the brake pad meetsthe sidewall.

A further braking mechanism is shown in FIG. 22A, which depicts a brakelever 114, a brake pad 116, brake cables 118, and an actuator assembly120, all situated beneath and attached to the pool cover. Upon actuationthe brake pivots and engages. Although depicted concentrically, theactuator may also be located eccentrically. The actuator may be moved bya water piston.

Further braking mechanisms are shown in FIG. 22B. In general, brakes maybe located anywhere at the periphery of the cover, preferably uniformlyabout the cover, and most preferably separated by ninety or one hundredand twenty degrees. Braking mechanisms may include an actuator 122, abrake pad 124, and counterweight hangars 126. Brakes may press againstthe coping, the pool sides, or against provided pressure plates.

In a further embodiment of the invention, a hydraulic brake may be used.In the these embodiments, a brake pad, which may be coated, may bepressed to the sidewall using hydraulic pressure. Even a cylinder ofrelatively modest diameter, for example, about 3 inches, may providehigh braking force with a minimal amount of pressure. In anotherembodiment, the brake may be a magnetic brake, which may be actuated andreleased through an electric current. One might also contemplate one ormore of these brake devices working in tandem, or with one as a primarybraking device and another as a backup mechanism.

In a further embodiment of the invention, the braking devices asdescribed above may be supplemented or replaced by additional hydraulicsupports. Additional hydraulic supports are shown, for example, in FIG.23. Preferably these additional hydraulic supports use water to providehydraulic pressure. The additional hydraulic supports may have the sameor different pumping mechanism as the lifting mechanism. The additionalhydraulic supports may be attached to the cover and to the bottom of thepool with hinges or in any other manner that allows them to be deployedwhen the cover is raised. FIG. 23 shows a side view of additionalhydraulic supports in a deployed state 121 and undeployed state 123.FIG. 1 shows additional hydraulic supports in a deployed state. FIG. 1also shows an optional elevating table. Although any number ofadditional supports may be used, preferably a plurality of additionalsupports may be disposed about the circumference of the bottom of thepool. These additional hydraulic supports use the efficient hydraulicpower to stabilize the cover.

In a further embodiment of the invention, a pool is stabilized by atleast four rack and gear assemblies as shown in FIG. 24. FIG. 24includes two gears 125. The gears may be constructed from any materialthat is desired, including but not limited to stainless steel, aluminum,and cast polyurethane. It was found that polyurethane is preferred.Although applicant does not wish to be bound by theory, it is believedthat the use of a polyurethane gear allows more complete contact of thegear with the rack 127. The rack 127 is cast into a leg that is placedin a corner of the pool. A wheel 129 maintains pressure between the rackand the gears. Each gear is attached to a rod 131. The rod may be, forexample, a stainless steel rod. An apparatus such as that shown in FIG.24 is attached to each end of the rod, forming a rectangular frame. Eachrod is preferably secured by a plate 133. The cover of the pool rests onand/or is secured to the rack and gear assemblies. When the cover israised, the gears on each rack and gear assembly turn in unison. Thisallows a cover of substantial size to be raised without height variationon the sides. Locking one gear will prevent movement of all of thegears, further stabilizing the cover.

A cylinder locking, stabilizing, and failsafe mechanism is shown in FIG.24A, which depicts a side cutaway view of a rack mounted to a centerpiston as the receiving end of a locking mechanism. The rack may beeither surface mounted or molded into a cylinder. The bottom portion mayhave an open channel without the recessed rack, which may be used as apressure relief failsafe to keep the piston from extending past adesired elevation. A further embodiment of a locking and failsafemechanism is shown in FIG. 24B. This includes a locking mechanism with afailsafe position that may be hydraulically or spring actuated.

There may also be pressure-release openings that prevent the piston fromextending above a safe elevation; these pressure-release openingseliminate the water used to provide lift pressure after the cover hasachieved a predetermined height, thereby preventing the center cylinderfrom lifting too far out of the water. In a further embodiment, theopenings are disposed along the long axis of the lift column of thepool, with a cross-sectional area at least as great as thecross-sectional area of the flow inlet. In a still further embodiment,the opening for the column is also configured to hold the rack, and therack does not extend the entire length of the column. In this way, afterthe column has elevated to a desired height, the absence of the rackallows water to flow through the rack opening, preventing further liftof the column.

It was surprisingly discovered that use of stabilizing mechanisms asshown in FIGS. 24A and 24B had the beneficial effect of eliminating theneed for a seal at the base of the lift cylinder. So long as sufficienthydraulic pressure is maintained to provide the initial lift of thecover, any detrimental effect of a leak related to depression of thecover over time is avoided by engaging the locking rack mechanism. Nodetrimental effect arises from water leakage, because water used in thelift cylinder can safely flow into the pool. This is a decided advantageover any prior mechanism, because the costly and inconvenientreplacement of a seal is eliminated.

The no-seal configuration of FIGS. 24A and 24B is further advantageousbecause it allows the cover to be stabilized with the use of only asingle hole, since no additional hole for other stabilizing cylinders isnecessary. Furthermore, rotations of the gear used to secure thecylinder may be measured and used to accurately determine the height ofthe cover. Finally, this configuration prevents rotation of the cover.

In a further embodiment, a cover may be secured by magnetic locks,either alone or as an additional securing mechanism with another lock.

FIG. 24D shows an additional stabilizer. It includes a stabilizing wheel135 with a spring-loaded compressor that presses the wheel into a detent137 formed at a desirable pool depth.

FIG. 24E shows an additional locking and support mechanism. Rack 139 isengaged by locking mechanism 141 at the bottom of the pool. The rack (ofwhich there may be a plurality in the pool) may be connected to thecover and may recess into a receiving cylinder 143 as the cover lowers.A view of the locking and support mechanism of 24E is shown in thecontext of a pool in FIG. 24F

FIG. 24G shows an additional support mechanism. A cylinder 145 isprovided with at least one groove 147, preferably a double helix groove,directs the cylinder through at least one cylinder guide 149.

It should be understood that these support mechanisms described hereinare generally secondary and supplemental to the support provided by thelifting cylinder, though they may be the primary or only support asdesired or necessary.

G. Safety Devices

Although they are not required in all embodiments of the invention, oneor more safety devices may be included in pools of the invention. Someof the safety features that may be incorporated include providing theperiphery of the cover with a pressure sensitive gasket. This gasketwill slow or stop the cover when it is in the midst of raising orlowering if the cover is being raised or lowered. A security device maybe included that requires a key, a code, or a combination of a key and acode prior to raising or lowering the cover. A sensor may be provided todetect movement of the water. If there is water movement and/ordisplacement, then the cover can be prevented from raising and lowering.This sensor may be, for example, an infrared sensor.

Other safety features may include an emergency bypass valve that allowsa hydraulic lifting mechanism to be raised using an alternate source ofwater pressure (such as a hose) to raise the cover in case of pumpfailure. Controls for the cover may be configured to automatically raisethe cover to the highest position at a certain time, or after apredefined period of non-use; for example, after non-use periods of oneminute, five minutes, 10 minutes, 20 minutes, 60 minutes, or intervalsthereof. An alarm may be configured to sound when the cover is about toraise and while the cover is raising.

Another safety feature may be a stand placed between the bottom of thepool and the cover. This stand may be affixed to the cover after it hasdescended to a certain level, so that a person maintaining the poolunder the cover is assured that the cover will remain in place.

The safety features of the pool may be designed so that they may beoverridden by the user if desired. This may be the case if, for example,a person in a wheelchair is to use the pool as a therapy pool. Thewheelchair-bound person moves onto the cover when it is at its highestelevation, the prohibition against moving the cover while pressure is onthe cover is overridden, and the person on the wheelchair is loweredinto the water.

H. Additional Features

Pools of the invention may have many beneficial features in addition tothose previously described herein. For example, applicant stresses thatalthough many embodiments herein have been described with respect topools that are round, embodiments of the invention are not so limitedand may be of substantially any shape, as shown in FIG. 25. For example,a pool may be a square, rectangle, oval, circle, triangle,parallelogram, or another other shape. Furthermore, a pool of theinvention may accompany a conventional pool and offer a pleasingalternative to the conventional pool, perhaps by including various swimand massage jets as described above. FIG. 26 depicts conventional poolsaccompanied by pools of the invention.

Although small size is not required, the modular construction of someembodiments of the invention makes transport and assembly of a pool easyand convenient. The components used to make a pool may be sufficientlylight to allow them to be carried by less than three people. They may besufficiently small to allow them to be carried through a normal housedoor. This allows a pool to be constructed, for example, in an areawhere a conventional pool may not be constructed due to accessibility orsize restraints. Ease of modular construction is independent of finalpool size.

Pools of the invention may be constructed indoors or out. In oneembodiment, a pool of the invention is constructed inside a gazebo orother small outbuilding. This allows the user to create a personalized,relaxing environment. The environment is aesthetically pleasing, and apool with a cover that raises and lowers is an interesting conversationpiece, in addition to all of the functional advantages alreadydescribed.

Pools of the invention may be equipped with an “automatic overflow”function. This could be made, for example, by having the center of thecover at an elevation slightly greater than the edges, allowing water toflow down and away from the cover. This water could flow into the pool,or, if there are barriers about the coping, away from the pool.

Pools of the invention may be accompanied by containers that are alsosubterranean and accompanied by lifting mechanisms. Their liftingmechanisms may be independent of those of the pool. For example, a sixfoot cube could be constructed, then placed into the ground with its ownhydraulic lift mechanism. Into the cube could be placed a refrigerator,stereo, entertainment equipment, and pool supplies. Installation of oneof these containers in tandem with a pool of the invention could allowan area with seemingly only a patio to quickly be converted to an areaof fun and leisure.

A pool of the invention may be incorporated into a home computernetwork. A user could program the pool's operation remotely. Forexample, the user could use the internet to set the cover to lower andthe water to heat at any desired time. The same could be done bytelephone. This would allow the pool user to keep the pool closed, safe,and sanitary during the time the user is at work, and yet the user couldstill come home to a heated, clean pool, hot tub, or rehabilitationcenter. The cover could also be set to raise at a desired time; thismight be useful, for instance, if the pool were rented for a particularperiod of time. Computer assistance would also be ideal for those poolsincorporating “dancing fountains.” These fountains may be integratedinto the cover and operated, for example, when the pool is about sixinches deep. They may be operated in conjunction with additional lightsof varied colors throughout the pool.

Existing pools may also be retrofit with covers of the invention. Thiscould be accomplished, for example, by cutting a hole in the existingpool bottom to insert a lifting mechanism.

A pool of the invention is highly favorable for vacation homes, beachhomes, summer homes, or other residences that may not be accessed duringthe entire year. Safety concerns attendant to a conventional pool may bealleviated by a pool that is locked in as a patio while the primary pooluser is not present. Because the water in the pool can be made to becompletely inaccessible while the primary user is not present, somemunicipalities might waive certain fencing restrictions on pools of theinvention.

A pool of the invention may be a freshwater pool or a saltwater pool. Ifthe pool is a saltwater pool, a chlorination device such as thoseavailable from Intellichlor® may be used to chlorinate the pool.

The pool may be designed to be self-cleaning. For example, if theskimmer is placed two inches below the water surface, the cover can beprogrammed to first lower to the depth that provides only a two-inchpool. A gasket could then seal this water from the remaining water inthe pool. The water in the pool could be agitated and cleaned, removingany dust and debris that might have accumulated on the cover. The covercould then proceed to lower, allowing the water in the pool to remainclean.

The design of the pool could also allow savings on energy and time usedto heat the pool. For example, if a pool only two feet deep were desiredto be heated, the pool could lower until the water is apparently twofeet deep, a gasket could seal that water from the remaining water, andthe visible water could be heated.

Although much of this disclosure has been directed to pools and tables,it is contemplated that the lift technology reported herein could beused to raise and lower storage devices as well. For example, anenclosure may be used to store such items as speakers, a television, abarbeque island, or gaming gear. This enclosure may have a liftmechanism as described above, enabling a user to raise and lower theenclosure at will. One could contemplate using such a device totransform a seemingly unremarkable outdoor space into a unique livingexperience, complete with entertainment. This could be accomplishedmerely be pressing a switch and allowing the enclosure to raise toground level. When lowered into the ground, the enclosure could becovered by a surface, such as grass or gravel, that masks the presenceof the enclosure. Such an enclosure might also be used for more mundanestorage applications. In a further aspect, a pool umbrella may bedepressed into the ground and raised by a cylinder as described herein.No enclosure would be required. Storage of the umbrella would beconvenient and would prevent weathering.

I. Controller

In some embodiments of the invention, the pool may include a controller.The controller will have the capability to raise and lower the pooldeck. The controller will provide signals to motorized valves 201, 202and 208 to enable a single pump 203 to either raise or lower the deck.At any allowable position the controller will activate a lockingmechanism 204 to physically lock the platform in the “deck” position.The controller will enable this lock once the platform has reached theallowable position. Various unallowable positions may will be programmedinto the controller to prevent the deck surface from stopping at variouslevels in the pool where it much block steps and other appurtenances. Inthis embodiment, when the deck is being lowered the controller willfirst disable the lock 204, reconfigure valves 201 and 202, open thelocking valve 208 and then start the pump 203 to move the platform.

In a further embodiment, the control will be able to stop the deck atseveral predefined positions. The controller will receive levelinformation from a platform mounted position transmitter 206. Thistransmitter may be, for example, ultrasonic, laser, or digital encoder.Once the user pushes a button 207 on the controller the controller willexamine the platform current position and the requested position. TheController will then configure the valves 201 and 202 for either a raiseor lower, open the locking valve 208, unlock the locking device 204,then start the deck pump 203. Once the deck reaches the desired locationthe controller will stop the pump, lock the locking device 204, andclose the locking valve 208. The controller will also not allow the userto select any unallowable points.

In a further embodiment the controller will allow the operator to stopthe deck at any location. The controller will also allow the user tomanually raise and lower the deck. The user would enable the controllerand then press the raise or lower buttons 209. The display on thecontroller would display the depth 210 and continuously show how thedepth is changing. Once the deck has reached the desired location theuser would release the direction button. The Controller would stop thedeck pump 203, lock the locking device 204, and close the locking valve208. The controller will also not allow the user to select anyunallowable points.

In a further embodiment the controller will know the position of thepool deck at all times. The controller system would have a positiontransmitter 206 which measure the distance from the bottom of the poolstructure to the current deck position. The pool depth could then becalculated by knowing the distance between the transmitter poolstructure, adding the know distance between the transmitter and the topof the deck, and accounting for the water surface level transmitted by awater level transmitter 211.

In a further embodiment, the controller will be provided with safetiesto ensure safe operation of the movable pool deck. These safeties wouldinclude, for example, but not be limited to the following:

i) Pool deck pump discharge pressure transmitter 212. This device wouldsense if the deck had jammed in the raising operation and shut down theoperation of the controller.

ii) Emergency stop push buttons 214. These switches would be locatedboth on the controller and in close proximity to the pool to shut downthe deck moving operation.

iii) Key switch operation 215. The controller would incorporate a keyswitch so that the controller would not operate without the key in theswitch and the switch held in the enable position. The switch would be aspring return to off so that an operator would be required to be presentat the controller during all deck movement operations. With a properauthorization code the requirement to hold the enable switch in theenable position could be bypassed and the controller will continue tooperate without the enable switch held in the enable position.

iv) Code. A code could also be used for pool deck operation in additionto or instead of the key switch. The operator could enter a passwordcode into the controller prior to deck movement operation.

v) Wave sensor 216. A wave sensor could be used to confirm there are nooccupants in the pool prior and during pool deck operation.

vi) An infrared sensor 217. An infrared sensor could also be used toconfirm there is nobody in the pool prior to pool deck movement.

In a further embodiment, the controller would be able to lock the deckin any allowable position. When the deck is in an allowable position thecontroller would be able to lock the deck into position with a lockingmechanism 204 to stabilize the deck and prevent the deck from “creeping”down due to possible leakage from the hydraulic elements. The lockmechanism could be located either at the edge of the deck, at the bottomof the pool, or on a supporting member.

The controller in this embodiment will be able to raise and lower anintegrated table in the pool cover 205. In the center of the pool deckis an integrated table. This table can be raised when the deck is in thefull up position. In one embodiment, the table may rotate freely, in a“lazy Susan” fashion. The table can also be lowered to fully utilize thedeck area, or when the deck is below the water surface. The table willhave two limit switches 213 to indicate a full up or full down positionof the table. The table will normally be raised and lowered up using thekeys 225 on the controller. The controller 219 will be able to interfacewith other pool devices and be able to communicate with othercomputers/Internet. The controller would be able to communicate withother pool components or computers. The protocols would include RS 485port 220 to allow the deck controller to talk to other pool equipment.The pool deck controller could then be integrated with other poolequipment to provide a complete pool control system.

An Ethernet connection 221 would also be available to allow thecontroller to either be configured by a browser type interface or allowother computers either locally or via the Internet to communicate withthe pool deck controller. This Ethernet port could also be connected toa service company or the manufacturer to allow remote diagnostics orsystem condition alerts.

Typically the controls would consist of two enclosures, a pool deckcontroller and an electric control box. The pool deck controller 219would typically normally be mounted indoors within sight of the pool.There would be a communications wire to connect the pool deck controllerto the electrical control box 229. The electrical control box would be aseparate box mounted at the pool equipment to allow high voltageconnection to pump(s), valves, and other sensors. “Service mode” is whencontrol is enabled at the electric control box. When in service mode thepool deck controller functions would be disabled and control would onlybe available at the electric control box. When in service mode theelectric control box would allow service personnel to operate allcomponents of the system for service and diagnostic purposes.

In the further embodiment, the pool deck controller 219 would havecustomer operator interface controls. The pool deck controller wouldhave a custom designed interface consisting of a display and variouslights and switches. The color display 222 could be a 3.5 inch ¼ VGA(QVGA) 320×240 pixels) resolution touch screen to display itemsincluding but not limited to pool deck level, table up or down, waterlevel, wave sensor information, upper level lock engaged, pool deckselector valves in up or down position, locking valve open/closed, pooldeck traveling up or down, or table traveling up or down. The controllerdisplay may incorporate a touch screen to allow operator input ofvarious functions and setpoints. The controller display may could alsobe simplified to a position setpoint slider and a small LCD deck levelreadout.

Controller switches may include, for example, a spring return enable offswitch 215, an emergency stop switch 214, a table/deck selector switch224, a deck up command button, a deck down command button 209, a tableup command button, a table down command button 225, several presetposition command buttons 207. Lights would indicate emergency stopswitch pressed 226, sequence fault 227 and in “service” mode 228. Thecontroller may send a level signal to a special LED readout 223 on theedge of the pool to indicate current pool depth. This LED may bemanufactured into a tile similar to the type of tile that surrounds thepool. There would be an audible alarm to alert the operator of a systemfault.

Pool Bottom Contour

FIG. 29 shows a cross-section of one preferred implementation of a pool300 having a movable cover 302. The pool 300 includes a water container304 having an open top 306 defined by a peripheral edge 308, a bottom310, and at least one sidewall 312. The water container 304 is adaptedto be filled with water near or up to the peripheral edge 308 or top ofthe at least one sidewall 312. The movable cover 302 also defines aneffective bottom when it is lowered into the water container 304,thereby allowing water to be on top of it. The cover 302 includes aplatform 314 with a top side and a bottom side. The platform 314 issized and adapted to fit within the peripheral edge 308 of the watercontainer 304. The platform 314 can be supported by one or more supportstructures 316, preferably mounted to the bottom side of the platform314.

The pool 300 further includes a single receiving cavity 318 arranged inthe bottom 310 of the water container 304, for receiving a single column320 connected with the bottom side of the platform 314. In operation,the single column 320 is at least partially displaceable from the singlereceiving cavity 318 to move the platform 314 upward, and at leastpartially replaceable in the single receiving cavity 318 to move theplatform 314 downward into the water container 304 toward the bottom 310of the water container 304.

The bottom 310 of the water container 304 has a predetermined contour inwhich the bottom 310 has a first downward slope 322 from the sidewall312 toward a lowest point 324 on the bottom 310 which can include adrain or other type of egress port, in which debris or other objects canaccumulate and be sent out of the water container 304. The bottom 310has a second downward slope 326 from an opening and gasket 328 of thesingle receiving cavity 318 toward the lowest point 324, to specificallyinhibit the debris or other objects from entering into the singlereceiving cavity 318.

In some preferred implementations, the angle or slope of the seconddownward slope 326 is greater than the angle or slope of the firstdownward slope 322, thereby creating a relatively small protrusion fromthe bottom 310 in which the single receiving cavity 318 is positioned.In some implementations, the second downward slope 326 and/or protrusionare a unitary part of the single receiving cavity. The first downwardslope 322 can include a number of angled slope areas, and can be shapedto accommodate the support structure 316 of the platform 302, whichforms the effective bottom of the pool 300 as it is lowered into the 304to any desired level from just below the surface of the water down tothe real bottom 310 of the water container. With this form, the pool 300and particularly the mechanism for moving the platform 314 up and downare kept clean and properly functioning.

Multiple Platforms

A pool as described herein may be implemented using multiple platforms,each being hydraulically actuated by a single cylinder. Each of themultiple platforms and respective hydraulic cylinders may be controlledindependently, while still coordinated for specific desired featuressuch as multiple, stepped depths or to achieve one continuous depthbetween the multiple platforms. Alternatively, the multiple platformsmay be connected to a common hydraulic actuation network forsimultaneous, connected and coordinated control.

A pool having multiple platforms can be made to form many differentshapes or open tops, as defined by a peripheral edge that can take anynumber of shapes. The pool includes a bottom and at least one sidewall.The open top can be filled with multiple platforms, each having a shape.The shape of each platform may be the same or may be different. Forexample, for an elongated, rectangular pool, the pool may contain two ormore squared platforms, each actuated by its own respective hydrauliccylinder. Preferably, the platforms are arranged side-by-side, and notone within another.

As described above, the multiple platforms can be independentlycontrolled, although in a coordinated, predetermined manner, to form aneffective bottom of the pool of any desired format. For example, themultiple platforms can be controlled to form a pool having multiplesimultaneous depths, such as a series of steps from a shallow depth tomore deeper depth(s), or a stepwise V-shape. Or, each of the multipleplatforms can be controlled in a coordinated manner to create a uniformeffective bottom of any depth, from several inches to many feet.

Prefabricated Container

The water container, or sidewalls thereof, may be formed as a unitarypiece, from a single sheet or collection of sheets of material,preferably of a plastic or fiberglass or fiber-reinforced material,which can be formed according to one or more forming technologies. Thewater container can also be made of stainless steel or other metal. Thewater container preferably has vertical side walls.

In one implementation, the water container or portion thereof is formedby thermoforming or vacuum forming. Alternatively, the container can becast or molded into form. The water container is adapted to be deliveredto the site and put together, rather than constructed on-site. Minorassembly may be requited, such as hooking up piping, pumps etc. In thecase where the size of the pool is large, the pool may be delivered intwo or more sections and put together on-site. In anotherimplementation, to manufacture the water container, first a gel coat isshot onto a mold, which is then shot with a fiber chop, and thenreinforced with reinforcement strips (manually glued on). Finally, theentire surface can be blasted with a coating bond it all in.

In yet another implementation, a material known as “G10” can be used.The G10 material includes two thin synthetic layers ( 1/16 inch) withfoam core. Large panels of G10 can be bolted together, and then wrappedwith tubes or other pretension w/e conduits. Then, the pretension wirecan be tightened to a predetermined tension for added stability.

All claims in this application, and all priority applications, includingbut not limited to original claims, are hereby incorporated in theirentirety into, and form a part of, the written description of theinvention. Applicants reserve the right to physically incorporate intothis specification any and all materials and information from any suchpatents, applications, publications, scientific articles, web sites,electronically available information, and other referenced materials ordocuments. Applicants reserve the right to physically incorporate intoany part of this document, including any part of the writtendescription, and the claims referred to above including but not limitedto any original claims.

As used herein and in the appended claims, the singular forms “a,” “an,”and “the” include plural reference unless the context clearly dictatesotherwise.

Subheadings herein are included for the benefit of the reader. Theyshould not be used to limit the invention.

The terms and expressions employed herein have been used as terms ofdescription and not of limitation, and there is no intention in the useof such terms and expressions, or any portions thereof, to exclude anyequivalents now know or later developed, whether or not such equivalentsare set forth or shown or described herein or whether or not suchequivalents are viewed as predictable, but it is recognized that variousmodifications are within the scope of the invention claimed, whether ornot those claims issued with or without alteration or amendment for anyreason. Thus, it shall be understood that, although the presentinvention has been specifically disclosed by preferred embodiments andoptional features, modifications and variations of the inventionsembodied therein or herein disclosed can be resorted to by those skilledin the art, and such modifications and variations are considered to bewithin the scope of the inventions disclosed and claimed herein.

Specific methods and compositions described herein are representative ofpreferred embodiments and are exemplary and not intended as limitationson the scope of the invention. Other objects, aspects, and embodimentswill occur to those skilled in the art upon consideration of thisspecification, and are encompassed within the spirit of the invention asdefined by the scope of the claims. Where examples are given, thedescription shall be construed to include but not to be limited to onlythose examples. It will be readily apparent to one skilled in the artthat varying substitutions and modifications may be made to theinvention disclosed herein without departing from the scope and spiritof the invention, and from the description of the inventions, includingthose illustratively set forth herein, it is manifest that variousmodifications and equivalents can be used to implement the concepts ofthe present invention without departing from its scope. A person ofordinary skill in the art will recognize that changes can be made inform and detail without departing from the spirit and the scope of theinvention. The described embodiments are to be considered in allrespects as illustrative and not restrictive. Thus, for example,additional embodiments are within the scope of the invention and withinthe following claims.

1. A pool comprising: a water container comprising an open top definedby a peripheral edge, a bottom, and at least one sidewall, a singlereceiving cavity being arranged in the bottom of the water container,the bottom having a contour shape comprising a first slope having afirst downward pitch between the sidewall and a lowest point in thebottom and a second slope having a second downward pitch between thesingle receiving cavity and the lowest point, the lowest pointcomprising an egress port from the water container; a platform with atop side and a bottom side, the platform being sized and adapted to fitwithin the peripheral edge of the water container; and a single columnconnected with the bottom side of the platform and arranged in thesingle receiving cavity, the single column being at least partiallydisplaceable from the single receiving cavity to move the platformupward, and at least partially replaceable in the single receivingcavity to move the platform downward.
 2. The pool in accordance withclaim 1, wherein a cross-sectional shape of at least a portion of anouter surface of the single column corresponds with a cross-sectionalshape of at least a portion of an inner surface of the single receivingcavity.
 3. The pool in accordance with claim 2, wherein thecross-sectional shape of the outer surface of the single column and thecross-sectional shape of the inner surface of the single receivingcavity is a shape selected from a group of shapes consisting of: circle,square, triangle, ellipse, rhombus, trapezoid, and parallelogram.
 4. Thepool in accordance with claim 1, further comprising a water flowmechanism to pump water into the single receiving cavity below thesingle column to at least partially displace the single column from thesingle receiving cavity, and to pump water out of the single receivingcavity to at least partially replace the single column into the singlereceiving cavity.
 5. The pool in accordance with claim 4, wherein thewater flow mechanism includes at least one pump, an inlet into thesingle receiving cavity, and an outlet from the single receiving cavity.6. The pool in accordance with claim 1, wherein the second downwardpitch is greater than the first downward pitch.
 7. The pool inaccordance with claim 1, wherein the single column includes a pressurerelease channel having an inlet in the bottom of the single column andan outlet on the outer surface of the single column at a distance abovethe bottom of the single column, the pressure release channel beingconfigured to allow water to flow from the single receiving cavity intothe water container when the outlet of the channel extends above a topedge of the single receiving cavity to release a predetermined amount ofpressure in the single receiving cavity.
 8. The pool in accordance withclaim 1, wherein the sidewall comprises a plurality of interlockingblocks, each block having at least one groove that, when aligned andcombined with at least other groove on an adjacent block, defines achannel.
 9. The pool in accordance with claim 8, wherein each of theplurality of blocks is formed of foam.
 10. The pool in accordance withclaim 1, wherein the water container comprises a unitary piece thatcomprises the peripheral edge, the bottom, and the at least onesidewall.
 11. The pool in accordance with claim 10, wherein the unitarypiece comprises one or more materials selected from a group consistingof plastic, fiberglass, fiber-reinforced material, stainless steel,metal, and foam.
 12. The pool in accordance with claim 1, wherein thesingle receiving cavity includes a single aperture proximate a bottom ofthe single receiving cavity that defines the inlet into and the outletfrom the single receiving cavity.
 13. A pool comprising: a watercontainer comprising an open top defined by a peripheral edge, a bottom,and at least one sidewall; two or more platforms, each with a top sideand a bottom side, the two or more platforms being sized and adapted tofit adjacently within the peripheral edge of the water container; two ormore receiving cavities arranged in the bottom of the water container,each of the two or more receiving cavities being sized and adapted toreceive a corresponding single column connected with the bottom side ofa corresponding one of the two or more platforms; and one or more waterflow mechanisms to flow water into the two or more single receivingcavities to at least partially displace the corresponding single columnfrom its single receiving cavity to move the corresponding platformupward, and to flow water out of the two or more single receivingcavities to at least partially insert the corresponding single columnfurther into its single receiving cavity to move the correspondingplatform downward.
 14. The pool in accordance with claim 13, wherein thebottom of the water container has a contour shape comprising a firstslope having a first downward pitch between the sidewall and a lowestpoint in the bottom and a second slope having a second downward pitchbetween the single receiving cavity and the lowest point, and the lowestpoint comprises an egress port from the water container.
 15. The pool inaccordance with claim 13, wherein the corresponding single columns areat least partially displaced from the two or more single receivingcavities when water received into the two or more single receivingcavity produces, in at least one of the two or more single receivingcavities below the corresponding single column, a pressure that exceedsa threshold pressure.
 16. The pool in accordance with claim 15, whereinthe threshold pressure is five pounds per square inch.
 17. The pool inaccordance with claim 13, further comprising a pool deck controller thatcontrols raising and lowering of the two or more platforms by passingcommands to the one or more water flow mechanisms.
 18. The pool inaccordance with claim 13, wherein the pool deck controller raises andlowers the two or more platforms independently of each other.
 19. Thepool in accordance with claim 13, wherein the pool deck controllerraises and lowers the two or more platforms in a coordinated manner. 20.An apparatus for use with a pool, the pool comprising a water containerhaving an open top defined by a peripheral edge, a bottom, and at leastone sidewall, a single receiving cavity being arranged in the bottom ofthe water container, the bottom having a contour shape comprising afirst slope having a first downward pitch between the sidewall and alowest point in the bottom and a second slope having a second downwardpitch between a second point on the bottom and the lowest point, thelowest point comprising an egress port from the water container; thepool further comprising a water flow mechanism to flow water, theapparatus comprising: a platform with a top side and a bottom side, theplatform being sized and adapted to fit within the peripheral edge ofthe water container; a single receiving cavity adapted to be arranged atthe second point in the bottom of the water container and having amechanism to receive and expel water from the water container; and asingle column connected with the bottom side of the platform and placedin the single receiving cavity, the single column configured to be atleast partially displaced from the single receiving cavity to move theplatform upward when the water flow mechanism flows water in to thesingle receiving cavity, and configured to be at least partiallyreplaced in the single receiving cavity to move the platform downwardwhen the water flow mechanism flows water out of the single receivingcavity.